This TSB article is being republished in its entirety to correct the Labor Operation Times listed.

ISSUE:

An exhaust leak at the exhaust manifolds may be evident on some vehicles. This may be due to heat causing a reduction in bolt torque on the exhaust manifolds.

ACTION:

Install new exhaust manifold bolts. Refer to the following Service Procedure and Part Application Chart for details.

SERVICE PROCEDURE

If an exhaust leak exists at the exhaust manifold due to a reduction in bolt torque, remove the manifold bolts and the exhaust manifold and check the overall flatness of the manifold. The manifold should not exceed 0.25mm (0.010″) out-of-flat. Refer to the appropriate model/year Service Manual for manifold removal procedures.

If the vehicle is covered under the emissions warranty period, replace the manifold if it is out-of-flat. If the vehicle is out of the emissions warranty period, resurface the exhaust manifold.

NOTE:

IF THE MANIFOLD IS TO BE RESURFACED, THE BOLTS MUST BE SHORTENED TO ACCOMMODATE THE EXHAUST MANIFOLD. THE BOLTS SHOULD HAVE THE LEADING “DOGPOINT” REMOVED TO PREVENT BOTTOMING INTO THE HOLE.

Install the manifold using new mounting hardware, but DO NOT USE WASHERS TO INSTALL THE MANIFOLD. Torque the bolts to 34-47 N-m (25-35 lb-ft).

NOTE:

THERE SHOULD NOT BE ANY TYPE OF GASKET USED BETWEEN THE EXHAUST MANIFOLD AND THE CYLINDER HEAD.

Check all exhaust system fittings loosened during repair for adequate tightness and allow engine to warm up. Recheck exhaust system for leaks and repair as required.

PART APPLICATION

Engine Size

Part

Part Number

Quantity

7.0L

Bolt – 3/8″-16×2.87

391730-S101

3

7.0L

Stud – 3/8″-16×4.10

391732-S101

7

7.0L

Bolt – 3/8″-16×1.74

391729-S101

4

7.0L

Stud – 3/8″-16×2.87

391845-S101

2

7.0L MFI/LPG

Manifold – RH

F1HZ-9430-B

1

7.0L MFI/LPG

Manifold – LH

F1HZ-9431-B

1

7.5L

Bolt – 3/8″-16×2.87

391730-S101

4

7.5L

Stud – 3/8″-16×4.10

391732-S101

4

7.5L

Stud – 3/8″-16×2.87

391845-S101

7

7.5L

Bolt – 3/8″-16×1.74

391729-S101

1 (F-Series)

7.5L

Stud – 3/8″-16×2.87

391845-S101

1 (Econoline)

7.5L E/F 250-350

Manifold – RH

F4TZ-9430-C

1

7.5L E/F 250-350

Manifold – LH

F4TZ-9431-C

1

7.5L F-53 S/D

Manifold – RH

F5TZ-9430-B

1

7.5L F-53 S/D

Manifold – LH

F5TZ-9431-C

1

7.5L CA Only

Manifold – RH

F6TZ-9430-NA

1

7.5L CA Only

Manifold – LH

F6TZ-9431-LA

1

PART NUMBER

PART NAME

391730-S101

Bolt

391732-S101

Stud

391729-S101

Bolt

391845-S101

Stud

F1HZ-9430-B

Exhaust Manifold

F4TZ-9430-C

Exhaust Manifold

F5TZ-9430-B

Exhaust Manifold

F1HZ-9431-B

Exhaust Manifold

F5TZ-9431-C

Exhaust Manifold

F6TZ-9430-NA

Exhaust Manifold

F4TZ-9431-C

Exhaust Manifold

F6TZ-9431-LA

Exhaust Manifold

OTHER APPLICABLE ARTICLES:

NONE

SUPERSEDES:

97-26-23

WARRANTY STATUS:

Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage And Emissions Warranty Coverage